1. Technical Field
The present disclosure relates to a semiconductor light emitting element.
2. Related Art
Nitride semiconductor light emitting elements have been widely used in recent years. In this type of semiconductor light emitting element, n-type and p-type nitride semiconductor layers are laminated over a sapphire substrate which is an insulating substrate, part of the p-type nitride semiconductor layer is removed to expose the n-type nitride semiconductor layer, an n electrode is formed on the exposed portion of the n-type nitride semiconductor layer, and a p electrode is formed over substantially the entire surface of the remaining p-type nitride semiconductor layer.
In a nitride semiconductor light emitting element in which n and p electrodes are formed on the same side of a substrate, which is the light extraction side, in order for the light to be emitted uniformly from the semiconductor layer side, a transparent p ohmic electrode is formed over substantially the entire surface of the p-type nitride semiconductor layer, and a pad electrode and extending electrodes having various shapes and extending from the pad electrode are formed over the p ohmic electrode, so that the extending electrodes diffuse the current uniformly to the p-type nitride semiconductor layer, which has relatively high resistance (JP2008-226866A, JP2008-244425A).
However, given today's need for nitride semiconductor light emitting elements that are larger, output more light, etc., it has been difficult to apply current uniformly over the entire light emitting face (that is, the p-type semiconductor layer in plan view), and to ensure uniform light emission.